Attempting to display the system dashboard generates a warning

If you go to the system dashboard it complains about misconfiguration, and the details begin:

We've detected a potential problem with JIRA's Dashboard configuration. Hide Close
Dashboard Diagnostics: Mismatched URL Scheme
JIRA is reporting that it is using the URL scheme 'http', which does not match the scheme used to run these diagnostics, 'https'. This is known to cause JIRA to construct URLs using an incorrect hostname, which will result in errors in the dashboard, among other issues.
The most common cause of this is the use of a reverse-proxy HTTP(S) server (often Apache or IIS) in front of the application server running JIRA. While this configuration is supported, some additional setup might be necessary in order to ensure that JIRA detects the correct scheme.
The following articles describe the issue and the steps you should take to ensure that your web server and app server are configured correctly:
Gadgets do not display correctly after upgrade to JIRA 4.0
Integrating JIRA with Apache
Integrating JIRA with Apache using SSL
If you believe this diagnosis is in error, or you have any other questions, please contact Atlassian Support.